Once again, it comes down to how much you trust the service provider. My Comcast agreement explicitly states that they will not sell or otherwise use my browsing and location information outside of a law enforcement subpoena or warrant. I have to believe them if I want to have a home internet connection; as of this news piece I'm certainly not going with AT&T DSL. Once again, Comcast could be lying to me but at least I have it on paper that they don't track and sell info. That's something that can be held over their head in court if necessary.

If people are that concerned about their privacy then trust shouldn't even be a factor. All of these privacy policies are worded in a way that leaves backdoors open and subject to change at any time without prior notice (ie: they'll tell you after the fact). Also, they're not going to give you ammunition to use against them in court. In theory those privacy policies are a nice little security blanket, but in practice they're usually worth little more than the actual paper they're printed on after you get through the wording and fine print.